1. Field of the Invention
The present invention is related generally to a method for fastening semiconductor components to substrates by diffusion welding wherein the surfaces to be joined are provided with a metallization and are pressed together while being heated. The invention also relates to an arrangement for implementing the method. The method and apparatus find particular use for large-area power semiconductors.
2. Description of the Related Art
A method is disclosed in German published application 33 25 355 wherein a metallization of a surface or area of a semiconductor component which is to joined to the substrate ensues by chemical deposition of the metal or by vapor deposition of the metal in a vacuum. In the German published application is also disclosed another method of this species wherein a metal film or foil is inserted between the surfaces of the components and the substrate that are to be joined to one another. The parts are then subjected to a diffusion welding process.
The disclosed method has disadvantages, however, in that the diffusion welding occurs in a vacuum chamber and requires a temperature of approximately 550 degrees C. and a pressing power of about 150 kp/cm.sup.2. Due to the different coefficients of thermal expansion in the individual parts, the high temperature load stresses the semiconductor components which result in corresponding curved or buckled portions in the finished product.